jashy247

Hey guys,

I have heard some 550i's with the RPI exhaust and LOVE the throatiness and sound of it, I was just wondering how the 550i will sound with the resonators removed. I was searching all day and couldnt find anything. Has anyone done this? Goes that moves on to my next question, RPI Exhaust or remove resonators? Any advice will be greatly appreciated! Thanks!

ktlocklear

remove resonators and post up vids of how it sounds.....I'm thinking about the same thing

jashy247

I was trying to avoid being the test dummy, has no one done this before...?

ktlocklear

ehh, c-mon...lol, j/k I don't want to be the test dummy either.

I did pop off the arm on the actuator flapper thing on the muffler that controls and opens the second exhaust port. Once I popped the arm off from the flapper, I just zip tied it open so it stays wide open. A lot more throaty this way over stock. If you haven't done this....test it out. Let the car idle, and reach under and grab a hold of the actuator arm and crack it open manually and you'll be able to hear a difference. Not much of a difference, but def noticeable and more throaty at idle and cruising

jashy247

Thats AWESOME! i didnt know the exhaust had the actuator flapper on my car. Ill test it out tomorrow first thing! Thanks for the advice.

If no one else steps up to the plate ill do it when I come back from my trip, Mid February! Cant WAIT!!!

Surf911S

Interesting read.

ktlocklear

No probs. Yeah, just take a peak under the car and you'll see the actuator on the muffler. To remove the arm from the lever takes a little effort. You'll see where it connects, but I found that the easiest thing was to just grind down the weld, which allowed the arm to pop right off of the lever. Then I just zip tied the lever to that bracket on the muffler body in the open position so it doesn't rattle. Once you pop the arm off of the lever the flapper inside the muffler port will just flap around and rattle if you don't tie it off in the open position. You'll see what I'm talking about once you take a look.

jashy247

So about the resonator delete vs. rpi, anyone have anymore insight?

ktlocklear

Magnaflow has a stainless catback system now avail for the 550...or will be avail soon. I haven't heard anyone mention it here though.

Magnaflow part # 16559

Here are a couple of vids......

http://www.magnaflow.com/04sound/spo...550i/550i.html


Here's some info on it........

http://www.modbargains.com/MagnaFlow...t-BMW-550i.htm

Now to start comparing it to RPI.

* RPI is axle back, MagnaFlow is Catback
* Prices are about the same
* Both are stainless
* MagnaFlow is bolt-on, RPI you have to cut
* MagnaFlow claims 9hp/ 12ft lb increase, what does RPI claim?
What else..sound, looks, etc?

Pagemaster

You dont have any pics do you? I have my stock muffler sitting on my garage floor and don't see anything that looks like a flapper.....I have a 2008 550i also.

I recently replaced the stock muffler with the RPI. For the most part the sound of the RPI is great, but I am getting some 1500-1900 rpm drone that is wearing on me. The RPI looks amazing, especially after I installed slightly shorter exhaust hangers. I am actually considering going back to stock but replacing the tips with something that looks like the RPI tips, Does anyone know of any good RPI-like stainless steel aftermarket exhaust tips that could be relatively easily added to the stock muffler?

Happy to answer any questions about the RPI that I can help with.....

Thanks!